You can form whatever opinion you like. But the general concenus and my personal experience is that the S5 battery life is excellent if not outstanding.
You would do well to ensure that your battery is fully charged and use a good third party battery monitor e.g, Gsam or a similar app. It only takes a few poorly behaved apps to put a large dent in any battery so you should look for wayward apps and try to avail yourself of battery saving features e.g. reduced screen brightness, timeouts, processor governors and so forth. And perhaps consider looking into inverted apps.